An Integrated Portable Multiplex Microchip Device for Fingerprinting Chemical Warfare Agents.

Karolina Petkovic,Yonggang Zhu,Anthony Swallow,Sheng Li,Justin Doward,Yuan Gao,Fiona Glenn,Januar Gotama,Michael Best,Mel Dell’Olio,Simon Ovendon,Robert Stewart

doi:10.3390/mi10090617

Abstract

The rapid and reliable detection of chemical and biological agents in the field is important for many applications such as national security, environmental monitoring, infectious diseases screening, and so on. Current commercially available devices may suffer from low field deployability, specificity, and reproducibility, as well as a high false alarm rate. This paper reports the development of a portable lab-on-a-chip device that could address these issues. The device integrates a polymer multiplexed microchip system, a contactless conductivity detector, a data acquisition and signal processing system, and a graphic/user interface. The samples are pre-treated by an on-chip capillary electrophoresis system. The separated analytes are detected by conductivity-based microsensors. Extensive studies are carried out to achieve satisfactory reproducibility of the microchip system. Chemical warfare agents soman (GD), sarin (GB), O-ethyl S-[2-diisoproylaminoethyl] methylphsophonothioate (VX), and their degradation products have been tested on the device. It was demonstrated that the device can fingerprint the tested chemical warfare agents. In addition, the detection of ricin and metal ions in water samples was demonstrated. Such a device could be used for the rapid and sensitive on-site detection of both chemical and biological agents in the future.

Highlights

Lab-on-a-chip (LOC) devices have the potential to revolutionize modern medicine, environmental monitoring, and a range of industrial applications due to their advantages such as portability, rapid analysis, automation, and reduced usage of sample and reagents [1,2,3,4,5]
To maximize the sensitivity of the conductivity detection, a higher mobility of the background electrolyte (BGE) counter-ion and a higher difference between the mobilities of a BGE co-ion and an analyte ion are desired. This difference should be minimal to satisfy the basic criteria of the capillary electrophoresis, as this difference usually leads to a peak shape deformation [39]
Following the Plackett–Burman experimental design method, and by testing several co-ions (MES, MOPSO), counter-ions (His, Arg, Tris), electroosmotic flow modifiers (TTAB, CTAB), the BGE selected for the detection of warfare agent degradation products in this study was 10 mM MES/His and 10 μM CTAB

Summary

Introduction

Lab-on-a-chip (LOC) devices have the potential to revolutionize modern medicine, environmental monitoring, and a range of industrial applications due to their advantages such as portability, rapid analysis, automation, and reduced usage of sample and reagents [1,2,3,4,5]. The research in the field has exploded over the last 20 years, resulting in numerous applications in medicine [6,7,8], food security [9], and environmental monitoring [10,11,12]. Chemical and biological warfare agents have been the subject of significant scientific research over the last 20 years due to the increased threat of terrorism and usage in war zones. Many detection techniques have been developed to identify chemical warfare agents (CWA) such as G-type and V-type nerve agents. The developed detection techniques include infrared spectroscopy, ion mobility spectroscopy, capillary electrophoresis (CE), GC-MS, and LC-MS [14,15]

Objectives

Methods

Results

Conclusion